Explorers discover deepwater gas seeps off US Atlantic coast!!!

NOAA ocean explorers used an advanced multibeam sonar mapping system on NOAA Ship Okeanos Explorer last month to discover and map the first deepwater gas seeps found off the U.S. Atlantic Coast north of Cape Hatteras. The seeps were found at water depths greater than 1,000 meters (3,300 feet). Based on preliminary information, scientists believe the seeps are likely emitting methane gas.

NOAA ocean explorers used an advanced multibeam sonar mapping system on NOAA Ship Okeanos Explorer last month to discover and map the first deepwater gas seeps found off the U.S. Atlantic Coast north of Cape Hatteras. The seeps were found at water depths greater than 1,000 meters (3,300 feet). Based on preliminary information, scientists believe the seeps are likely emitting methane gas.

"It's important to find and understand such seeps because they have global significance for the transfer of methane carbon from long-term storage in ocean-floor sediments into the ocean and atmosphere," said Carolyn Ruppel, Ph.D., chief of the USGS' Gas Hydrates Project. "Methane released into the water column is often oxidized to carbon dioxide, leading to changes in ocean chemistry, such as ocean acidification." The seeps were mapped between Nov. 2 and 20 at three locations with water depths of 1,000 to 1,600 meters (3,300 to 5,250 feet). Approximately 25 distinct seafloor gas seeps were identified based on plumes rising into the water column as high as 1,100 meters (3,600 feet). The sites are between 147 and 163 kilometers (91 and 101 miles) off shore, with one site east of Cape Henry, Va., and two sites south and southeast of Nantucket Island, Mass. "NOAA tested the ship's multibeam sonar last year in the Gulf of Mexico and confirmed its advanced signal processing made it a highly capable new tool to detect gaseous seeps at great depths and over wide areas," said Robert Detrick, Ph.D., assistant administrator of NOAA Research. "This technology and the information it delivers is extremely valuable to researchers and ocean resource managers in NOAA, in other agencies, and across the nation."